Fe(III)-salen complex supported on dendrimer functionalized magnetite nanoparticles as a highly active and selective catalyst for the green oxidation of sulfides

In this study, we reported the preparation of polyamidoamine-modified magnetite nanoparticles and their use for the immobilization of Fe(III)-salen complex to form a novel magnetic catalyst. The prepared catalyst was characterized by some modern techniques i.e. Fourier transform infrared spectroscopy (FT-IR), thermogravimetric analysis (TGA), N-2 adsorption-desorption analysis, X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy-dispersive X-ray spectroscopy (EDX), X-ray photoelectron spectroscopy (XPS), vibrating sample magnetometry (VSM), and inductively couple plasma atomic emission spectroscopy (ICP-AES). The catalyst showed excellent activity and selectivity for the oxidation of sulfides to sulfoxides (conversion 87-100%, selectivity 82-100%) using H2O2 (30% w/w) as oxidant in aqueous medium at 50 degrees C. Furthermore, the catalyst could be recovered in a facile manner from the reaction mixture by using a magnet and reused for five cycles with high catalytic stability.